1. Field Of The Invention
The invention relates to an adjustment device for artificial limbs, more particularly to an adjustment device by which the gravitational equilibrium of an artificial limb incorporating the device can be easily adjusted.
2. Description Of The Related Art
Although many improvements have been made in the construction of artificial limbs, there is still much room left for improvement, particularly in the construction of joints for artificial knees and ankles so as to suit the joints to the wearer's body dimensions and walking conditions. Generally, the upper and/or lower portions of artificial joints are provided with an adjustment device. Referring to FIG. 1, an adjustment device for an artificial limb, as disclosed in U.S. Pat. No. 4,676,800 of the applicant, is shown to comprise a coupling member A to be connected to an upper joint portion of an artificial limb and having a circular joint projection al on a top end. A cylindrical member B has an open section at an upper end to fixedly couple the same with a lower portion of an artificial limb. The cylindrical member B further includes a lower end having an annular recess b1 provided with a plurality of cavities and through openings formed therein. Screw bolts C are received in the cavities of the cylindrical member B and extend into the annular recess b1 through the through openings to couple the cylindrical member B with the joint projection al of the coupling member A. By adjusting the screw bolts C, the cylindrical member B can be tilted relative to the coupling member A so as to easily adjust the center of gravity or the gravitational equilibrium of an artificial limb incorporating the device.
One of the disadvantages of this conventional adjustment device is that adjustment of the gravitational equilibrium is achieved only by varying the angle of tilt of the cylindrical member B relative to the coupling member A. Thus, simple lateral adjustment of the position of the cylindrical member B relative to the coupling member A is not possible.